1. Technical Field
The present invention relates to message handling systems and more particularly to a technique for interfacing two different message handling systems.
2. Discussion
The electronic transfer of message data is an increasingly important means of communication. It has many advantages over conventional methods such as mail and the telephone. As a result, a number of message handling systems have been developed to meet the needs of electronic message transfer for various categories of users. For example, one message handling system used in the United States is known as E-mail. An international message handling system, commonly used in Europe, is known as the International Standards Organization (ISO) Advanced Communications System (ADCOMMS) X.400 message handling system. Both of these systems are considered informal systems since neither is accepted as a formal system for record communications in accordance with United States Government message standards.
In contrast, formal message handling systems include those systems approved as "record communication" systems by the United States Government. One formal message handling system developed by the U.S. Department of Defense is referred to as the AUTODIN network. This is a system for implementing record communications by providing for end-to-end accountability of all messages. That is, a record is kept of every point a message goes into the system so that no message in the system is ever lost. Various types of standards exist for Department of Defense AUTODIN messages including those commonly known as Allied Communications Publication (ACP) 127; JANAP 128; and DOI-103. These standards set up criteria for the format of the message including the format of the header of the message, the body of the message and the end of the message, as well as the contents, the routing information on the header format, the operator signals, the precedence of the message and classification of the message.
One limitation of message handling systems is that they are generally self-contained systems so that messages cannot cross over from one system into the other. Some systems for interfacing two different message handling systems, known as "gateways" have been developed. However, their use has been primarily restricted to interfacing informal systems with each other, and have not been usable for interfacing two formal systems, or a formal and an informal system. In general, this is because the strict requirements of the formal systems have been heretofore considered substantially incompatible with the informal system messages.
Thus, it would be desirable to provide a means for interfacing two different message handling systems. It would also be desirable to provide a system for providing an interface between formal and informal message handling systems or between two different formal message handling systems which preserves the integrity of the message while satisfying the constraints of the respective message handling systems.